ok when is it nesscesary to get your car retuned?? like if you change any little part of your turbo setup do you need to go get a retune?? thanx for the help in advance

 

depends on what that "little part" is

 

well ok i changed the header and wastegate from a 38mm to a 42 mm and left everything else alone! but thats what i did. ok so here is the ? refrased what components would entail the need for a retune??

 

I'm not going to sit here and list everything that would require a retune and why. That is a big part of the research that you should be doing on your own.

As for specifics, what is the difference between the manifold (not header) that you're running now compared to the old one. And, does the wastegate have a different spring in?